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(N0- Model.) 2 Sheets-Sheet 1.

J. MAOTEAR.

REVOLVING FURNACE FOR GHEMIGAL PROCESSES. No. 361,429;

Patented Apr. 19, 1887.

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JAMES MAGTEAR, OF NVESTMINSTER, COUNTY OF MIDDLESEX, ENGLAND.

REVOLVING FURNACE FOR CHEMICAL PROCESSES.

SPECIFICATION forming part of Letters Patent No. 361,429, dated April19, 1887.

Application filed August 19, 1886. Serial No. 211,273. (No model.)Patented in England May 17, 1876, No. 2,073, and in France November 14,1876, No. 115,500. i

To all whom, it may concern;

Be it known that I, J AMES MAOTEAR, a subject of the Queen of GreatBritain and Ireland, and a resident of Westminster, county of Middlesex,England, have invented certain Improvements in Furnaces for ChemicalProcesses, (for which I have obtained a British patent, dated May 17,1876, No. 2,073, and a French patent, dated November 14, 1876, N 0.115,500,) of which the following is a specification.

My said invention relates to furnaces which, when made with theimprovements comprised in it, are advantageously applicable in themanufacture of alkaline carbonates for the process known as balling, forroasting or calcining soda-ash, or alkali, or carbonate of potash, andfor other similar operations, and also in the obtainment of copper bywhat is known as the wet process, for calcining the burnt copper orewit-h salt.

My improvements are applied to a furnace having a horizontal circularrevolving bottom made of iron, lined with fire-brick or other suitablerefractory material, and formed with a raised rim round the outer edge.

My invention consists, principally, in providing for the withdrawal ofthe finished charges of materials down through the center of thefurnace-bottom.

In a modification of the improved furnace which I prefer the fire-gasesare led into the furnace-space between the revolving bottom and roof,through openings at one side, and pass toward the opposite side, findingegress by two firms separated a short distance from each other, whilestirring apparatus 'is arranged in the part of the furnace-space betweenthe two exit-fines.

Figure 1 of the drawings is ahorizont'al section of the furnace, andFig. 2 is a corresponding vertical section.

The circular furnace bottom 1 consists of plate-iron lined withfire-brick, and is fixed on frame-pieces 2, which are fitted with wheel3, arranged to run on a circular flanged tramplate, 4, fixed beneath thefurnace. The furnace-bottom 1 is made with a raised rim, 5, and iscovered by a roof or arch, 6, of firebrick carried by arc-shaped girders7, which are supported on pillars 8. (Indicated by dotted lines in Fig.1.) Two fire-places, 9, communicate by a passage, 10, with thereverberatory chamber or space inclosed between the roof or arch 6 andthe circular bottom, and afterthe fire-gases have acted in that chamberthey pass off by two 'eXit-flues, 11, nearly opposite to theinlet-passage 10.

For charging the furnace one or more openings (not shown in thedrawings) which are closed when the furnace is in operation are providedat any convenient part of the roof or arch 6. The discharge-aperture isa cylindrical or nearly cylindrical opening, 12, made quite through thebottom 1 and its lining at the center, and this opening 12 is fittedwith an iron casing, 13, which projects below the bottom. A somewhatlarger opening, 14, is formed through the roof or arch 6, and is fittedwith an iron lining. The closing detail is an iron cylinder, 15, whichis jacketed with fire-brick or other refractory material, and when inthe closing position, as shown in Fig. 2, rests on the top edge of theiron lining of the discharge-opening 12 in the furnace-bottom, while itsupper part closes the opening 14. in the roof 6. The cylindrical closingdetail or valve 15 is made with two sets of arms, 16 17, to the upperset of which there is at tached an eyebolt for the connection of achain, 18, for raising the valve, while to the lower set, 17, there isattached a spindle, 19, which passes through a guide, 20, fixed by armsin the'opening 12 below. Air is allowed to pass up through thedischarge-opening12 and through the'valve 15, so as to prevent the metalparts from becoming overheated.

The discharge-aperture 12 is opened to the interior of thefurnace-chamber by raising the cylindrical valve 15 into the opening orrecess 14. in the roof or arch 6, and the contents of the furnace maythen be discharged into a wagon placed beneath the furnace, or into anysuitable receptacle.

- The stirring apparatus is arranged to act between the central valve,15, and the outer rim, 5, of the furnace-bottom at the part between thetwo exit-fiues 11, and it comprises a set of forks, 21, fixed on thelower ends of vertical shaft-s 22,, which are held in a frame,

23, and geared together by spur-wheels 24 at their upper ends, so as torotate in alternate directions, the forks 21, which are disposeddiametrically, being arranged so as not to interfere with each other,although they are large enough to work over overlapping areas.

The stirring apparatus can be raised out of action or lowered more orless, as may he required, the frame 23 being fitted to slide in verticalguides 25 on a fixed framing, and being formed with vertical racks26,with which gear pinions on a horizontal shaft, 27, arranged to beturned by means of a crank-handle. The driving-power is applied to theoutermost of the vertical stirrer-shafts 22, which is elongated to passup through a bevel-wheel, 28, to which it is geared by a groove andfeather admitting of its vertical movement with the frame 23. Thebevel-wheel 27 gears with a bevel-wheel on a short horizontal shaft, 29,driven as here inhefore described.

The finished charges of materials may be pushed toward the centraldisehargeoutlet, 12, by means of scrapers or other implements worked byhand through the openings hereinbefore referred to, as for charging inthe materials. I, however, prefer to use mechanical dischargingapparatus of the kind shown in the drawings, and which comprises aseries of pushers or scrapers, 30, attached to an endless chain, 31,carried and moved by pulleys 32 on the lower ends of vertical shafts 3334. These shafts 33 34 are carried by a frame, 35, which is fitted towork in Vertical guides 36, and has racks 37 on it in gear with pinions38 on a horizontal shaft, 39, so that it can be raised or lowered, asrequired, by means of a crankhandle.

The discharging apparatus is worked by means of one, 33, of the verticalshafts, which is elongated to pass up through a bevel-wheel, 40,connected to it bya groove and feather to admit of the vertical movementof the frame 35. The bevel wheel 40 is in gear with a bevel-wheel, 41 ona horizontal shaft, 42, which has also on it a spur-wheel, 43, gearingwith a spur-wheel, 44, on the horizontal shaft 29 of the stirringapparatus. The shaft 42 has on it clutches in connection with the wheels41 and 43, so that either can be put into or out from gear, as required,and this shaft 42 is itself driven by bevel-wheels 45 from a verticalshaft, 46, geared by bevel-wheels 47 to the shaft 48, which impartsrotation to the furnace-bottom 1, and is driven by means of a pulley andbelt, or otherwise, from any suitable prime mover. The furnace-bottom 1is turned by means of a pinion, 49, on the shaft 48, and gearing with acircular rack, 50, fixed to the framing of the furnace-bottom. A gutter,51, is formed round the outside of the rim 5 ofthe furnace-bottom tocontain loose materials from the inside of the furnace, or sand, intowhich the vertical flange of the girders 7 dips, so as to form a closedconnection between the rotating bottom 1 and fixed roof or arch (3 ofthe furnace, as usual in furnaces with rotating bottoms.

\Vhat I claim as my invention is 1. In a furnace for chemical processes,the combination of'a revolving bottom having a central discharge-openingwith means for closing the said opening, substantially as herein setforth.

2. As means for closing acentral discharge opening in a revolvingchemical-furnace bottom, a cylinder working in an opening in thefurnaceroof, and when closed occupying the space between the roofopeningand the discharge opening, substantially as herein set forth.

In testimony whereofl have signed my name to this specification in thepresence of two subscribing witnesses.

JA MES MAGTEAR.

\Vitnesses:

CHARLES AUBREY DAY, London, England. FREDERIC J nouns,

Clerk.

